[Ffmpeg-devel-irc] ffmpeg.log.20140705

[burek]

[02:05] <sbujnak> Hi, how do I convert any audio to mono? Currently I'm using aformat with following parameters: sample_fmts=flt:sample_rates=11025:channel_layouts=mono but it gives me error: http://pastebin.com/raw.php?i=7RvJJ0R4
[02:11] <c_14> https://trac.ffmpeg.org/wiki/AudioChannelManipulation
[02:24] <waressearcher2> I have video and in some places where its bright its quite too bright but in other places where its dark its really dark, can there be done something ? if I try to increase brightness to make dark parts brighter those bright parts are become really bright or on the other hand if I decrease brightness those dark parts are become really dark, or
[02:24] <waressearcher2>  should I cut out bright and dark parts and decrease and increase brightness in every of them separately ? is there any filter that can make average brightness on overall video ?
[03:47] <Jackster_> "Error while opening decoder for input stream #0:2 : Resource temporarily unavailable" I guess I can't open FFMPEG to many times? I have it running 5 transcodes and now this pops up on the 6th
[06:14] <portablejim> Is there a way to get ffmpeg to encode to mp3 at very-very low bitrates?
[06:36] <Jackster_> How can I make FFMPEG save a debug file? Need as much info as I can on a problem
[06:40] <Jackster_> ah got it
[06:51] <vkrishn> JEEB, https://dpaste.de/SxUA, from ffmpeg.static.32bit.2014-07-04
[07:41] <MarcelvanLeeuwen> Hi, first I was trying to encode with Handbrake on my server but i could build Handbrake from source. Then i discovered FFmpeg in the ClearOS-contribs repos. So i want to try to do some encoding with FFmpeg.
[07:43] <waressearcher2> what are you waiting for ? christmass ?
[07:44] <MarcelvanLeeuwen> Sorry?
[07:44] <MarcelvanLeeuwen> is there some batch script were i can put a movie in a directory and then FFmpeg automatically encodes the movie?
[07:47] <waressearcher2> you should use options
[07:48] <waressearcher2> scripts can't know what you want to achieve
[07:48] <vkrishn> MarcelvanLeeuwen, there could be more ways, but I would write a simple cron script+ using ffmpeg preset
[07:49] <MarcelvanLeeuwen> okay
[07:50] <MarcelvanLeeuwen> there is no example?
[08:07] <MarcelvanLeeuwen> ffmpeg -i input -c:v libx264 What means the -c:v?
[08:07] <sfan5> -c:v sets the video codec
[08:09] <MarcelvanLeeuwen> v = videocodec?
[08:09] <MarcelvanLeeuwen> so with audio its -c:a
[08:09] <MarcelvanLeeuwen> its a selector
[08:17] <sfan5> yes. v = video, a = audio, s = subtitles
[08:19] <MarcelvanLeeuwen> ah, also subs!
[08:37] <MarcelvanLeeuwen> is it possible to slect a stream? thus -c:a stream copy?
[08:38] <MarcelvanLeeuwen> *select
[09:06] <relaxed> MarcelvanLeeuwen: -c:a:0 for the first audio stream
[09:06] <relaxed> read the fine manual
[09:10] <MarcelvanLeeuwen> yes ive found h264 encode manual
[09:10] <MarcelvanLeeuwen> already testing!
[09:11] <MarcelvanLeeuwen> for so far Im very pleased
[09:34] <MarcelvanLeeuwen> what means the q=25 when encoding? quality? if set -crf 22
[09:39] <MarcelvanLeeuwen> * Ive set -crf 22
[10:23] <waressearcher2> are options "-c:v libx264" and "-c:v h264" the same ?
[10:29] <Filarius> hello, how I can set ffmpeg do not stop if I loop on same image what I use to store frames for video ? Seems sometime ffmpeg can`t access file because of it was blocked by writing http://pastebin.com/zzCxB4C4
[11:03] <waressearcher2> if I create 1920x1080 h264 video from high resolution photos, they are converted to images of 1920x1080 and in png format, what video bitrate should I use ? -vb 3000k ? -vb 5000k ?
[11:10] <sfan5> better use -crf
[11:10] <sfan5> crf will make sure every one of your photos is encodec in the same level of quality without wasting any data
[11:11] <sfan5> encoded*
[11:11] <waressearcher2> so that what is -crf for ?
[11:11] <sfan5> http://slhck.info/articles/crf
[11:11] <waressearcher2> so its not in "man ffmpeg-all" ?
[11:12] <sfan5> https://trac.ffmpeg.org/wiki/x264EncodingGuide
[11:12] <sfan5> I don't know
[11:12] <waressearcher2> what if I use "-vcodec mpeg4" can I still use "-crf" ?
[11:13] <sfan5> IIRC only libx264 supports crf
[11:18] <waressearcher2> also related question: I tryed to make video from 66 photos of resolution 1920x1080, they are all in png format, I used that command: "cat *.png | ffmpeg -f image2pipe -vcodec png -r .45 -i - -vcodec h264 -vb 5000k -r 25 -y -f avi video.avi", I run it on netbook with 1GB ram and after ffmpeg process consumed about 800MB of ram it crashes, why ? is
[11:18] <waressearcher2>  it because of x264 codec ?
[11:20] <sfan5> probably
[11:21] <waressearcher2> because I tryed to the same with "-vcodec mpeg4" and process ffmpeg consumed only 100MB of ram
[11:22] <waressearcher2> can I create good quality 1920x1080 video from images using "-vcodec mpeg4" codec ?
[11:22] <waressearcher2> or I should use x264 ?
[11:24] <sfan5> H.264 is better than MPEG4
[11:27] <waressearcher2> can't afford to use h.264 with more resolution that 1280x720
[11:48] <MarcelvanLeeuwen> is it possible to remove the black bars?
[11:49] <saste> MarcelvanLeeuwen, crop filter (need transcode)
[11:49] <saste> MarcelvanLeeuwen, also see cropdetect
[11:49] <MarcelvanLeeuwen> okay
[11:59] <MarcelvanLeeuwen> you first have to cropdetect and set the founded value with -vf crop=?
[12:05] <Filarius> how to ask ffmpeg to ignore files blocked by writing while process image sequence ?
[12:06] <Filarius> http://pastebin.com/4PG6tGRv
[12:12] <Filarius> with this ffmpeg at some time crash with
[12:12] <Filarius> "could not open file" error
[13:17] <vkrishn> JEEB, https://dpaste.de/SxUA, from ffmpeg.static.32bit.2014-07-04
[13:18] <vkrishn> I am also trying to go through the docs
[13:18] <vkrishn> and also trying some preset options in winff
[13:18] <MarcelvanLeeuwen> uses FFmpeg multithreading or is it using a single thread?
[13:19] <sacarasc> vkrishn: What are you trying to do?
[13:19] <sacarasc> MarcelvanLeeuwen: Depending on which codecs you use, it might default to multithreading.
[13:20] <MarcelvanLeeuwen> libx264
[13:20] <sacarasc> That defaults to multithreaded with as many threads as your CPU can handle.
[13:20] <vkrishn> sacarasc, trying to re-encode newer mp4 for older mobile (Dell xcd35)
[13:21] <sacarasc> What does the device support?
[13:21] <MarcelvanLeeuwen> if i check with top my cpu uses just 17% of its total resources&
[13:22] <vkrishn> https://dpaste.de/SxUA is mp4 that plays on xcd35
[13:22] <sacarasc> What version of ffmpeg are you using, MarcelvanLeeuwen?
[13:22] <MarcelvanLeeuwen> checking
[13:22] <vkrishn> ffmpeg.static.32bit.2014-07-04
[13:22] <vkrishn> ooops
[13:23] <MarcelvanLeeuwen> version 2.0.2
[13:25] <sacarasc> vkrishn: Try this, no guarantee, but it should work... ffmpeg -i ilikecheese.mp4 -c:a aac -b:a 90k -c:v libx264 -profile:v baseline -b:v 300k -preset:v slow -vf scale=400:-1 ilikecheese_mobile.mp4
[13:26] <sacarasc> MarcelvanLeeuwen: What is your source file?
[13:26] <vkrishn> sacarasc, thanks
[13:26] <MarcelvanLeeuwen> you meann source video file?
[13:26] <sacarasc> Yeah.
[13:26] <MarcelvanLeeuwen> checking
[13:28] <MarcelvanLeeuwen> h264/AVC
[13:28] <vkrishn> sacarasc, encoder 'aac' is experimental but experimental codecs are not enabled, add '-strict -2' if you want to use it.
[13:28] <vkrishn> Alternatively use the non experimental encoder 'libvo_aacenc'
[13:29] <sacarasc> According to https://trac.ffmpeg.org/wiki/GuidelinesHighQualityAudio the inbuilt one is better than libvo_aacenc, so you should probably just add that bit to the command.
[13:33] <vkrishn> would be nice if http://ffmpeg.gusari.org/static/docs was also available (tar files with html docs)
[13:34] <MarcelvanLeeuwen> i also have plex server installed i can encode a movie with ffmpeg and watch a movie (encode mode) at the same time&.
[13:34] <vkrishn> or pdf
[13:44] <MarcelvanLeeuwen> hmm you can also use -thread 0
[13:47] <MarcelvanLeeuwen> source is mkv 1080p h264/avc
[13:47] <MarcelvanLeeuwen> i encode to a smaller mkv with dts and subs
[13:48] <MarcelvanLeeuwen> Ive remuxed the orignal blu-ray to mkv with makemkv
[13:53] <sacarasc> MarcelvanLeeuwen: Add -threads 0 to the input options as well as the output ones.
[13:54] <MarcelvanLeeuwen> I will try after my test encode what now is running&
[13:54] <MarcelvanLeeuwen> I will inform you&
[13:56] <sacarasc> 1080p takes quite a bit to decode, so that could be where the bottleneck is.
[13:56] <MarcelvanLeeuwen> okay
[13:57] <MarcelvanLeeuwen> there is also a positive site.., now iahve enough power left to watch movies on Plex
[13:58] <sacarasc> I like Plex, but I do not like my slow ass mobile Internet on my phone. :D
[13:58] <MarcelvanLeeuwen> lol
[14:03] <MarcelvanLeeuwen> http://prntscr.com/3zlyiw
[14:03] <MarcelvanLeeuwen> see this screenshot of top
[19:22] <Extensa5630G> where to get the ffmpeg that has clear and featured GUI?i ended up downloading the one that is used from the cmd
[19:22] <Extensa5630G> I use Win7
[19:29] <sacarasc> There is no official GUI for ffmpeg.
[21:49] <alexd457> hi, I understand that seeking of a compressed format like wmav2 inside asf container is inherently imprecise. However, is there anything I can do to make it more precise?
[21:58] <alexd457> I meant when playing the asf in a player (eg, silverlight), i'd like the seeking to be more precise
[22:22] <felixf> Question: If I define my output codec to be -vcodec libx264 which happens to be the same as in the input video codec, does it behave identically to -vcodec copy or does a decode/reencode occur?
[22:49] <c_14> a decode/reencode occurs
[00:00] --- Sun Jul  6 2014